ABSTRACT
There are many extended-spectrum beta-lactamase (ESBL)-producing isolates of Klebsiella
pneumoniae in Thailand. In this study, we attempted to determine whether there was a correlation between
ESBL phenotypes and genotypes of ESBL-producing K. pneumoniae from 30 patients hospitalized at Siriraj
Hospital, Thailand. The ESBL phenotypes and genotypes were detected by using an antimicrobial susceptibility
test and a polymerase chain reaction, respectively. We found that the phenotypic resistance to cefotaxime,
ceftazidime, and ceftriaxone of ESBL-producing isolates may provide information concerning the correlation
with the presence of blaSHV, blaCTX-M, or blaVEB-1-like genes (p < 0.05), but not the blaTEM gene (p > 0.05). A
good correlation between the phenotypes and genotypes of ESBLs may provide the guidelines for selecting
appropriate antimicrobial agents for empirical treatment before obtaining the susceptibility results.